Electrical connectors



Nov. 17, 1964 w. M. HENNESSEY ELECTRICAL CONNECTORS Filed April 11, 1962 SHRUNK AND HARDENED INVENTOR. WILLIAM M. HENNESSEY ATTORNEY United States Patent Oflice 3,157,449 Patented Nov. 17, 1964 3,157,449 ELECTRICAL CONNECTORS William M. Hennessey, Roslyn, Pa, assignor to Burroughs Corporation, Detroit, Mich, a corporation of Michigan Filed Apr. 11, 1962, Ser. No. 186,699 2 Claims. (Cl. 339-66) This invention relates to electrical connectors and particularly to miniaturized electrical connectors.

The modern trend in miniaturization of electronic components has created special problems in electrical connectors which have been reduced in size and Weight to the point where they comprise thin, fragile bodies of insulating material which carry exceedingly fragile electrical contact members. Because of the small size of the parts and because of their fragility, there not presently available a strong, rugged connector assembly which is capable of being made and broken many times as required, for example, in testing electronic apparatus during assembly. Under some circumstances, for example in magnetic core memory assemblies made up of many memory planes, a very expensive memory unit can be rendered worthless by a connector which is broken during testing of one of the planes.

Accordingly, the objects of the present invention are directed toward the provision of improved electrical connectors which can be made as small and fragile as required while retaining ample ruggedness and durability.

Briefly, a connector embodying the invention includes first and second mating parts, each of which includes an insulating body and electrical contact means, the respective contact means being adapted to make contact with each other to eiiect the desired connection. A sleeve of resilient insulating material is fitted over the first mating part with a portion engaging the insulating body thereof, and the remainder extending axially beyond the end of the insulating body and surrounding preferably the entire length of the electrical contact means carried thereby. This extension of the sleeve is thus adapted to surround a considerable portion of the second part as it is brought into engagement with the first part when a connection is made. Thus, the sleeve acts as a guide for the second part as it engages the first and, in addition, holds both parts securely with respect to each other when they engage each other.

The insulating sleeve is of such material that the portion which surrounds and engages the insulating body of the first connector part can be treated to shrink and harden it to provide a rugged tight fit, while the extension portion which acts as a guide for the second mating part is allowed to retain its resilience.

The invention is described in greater detail by reference to the drawing wherein:

FIG. 1 is a perspective view of a connector arrangement embodying the invention and a portion of a typical piece of apparatus with which it may be used; and

FIG. 2 is a perspective View of the connector apparatus of the invention showing the connector parts assembled.

A connector arrangement embodying the invention and shown in the drawing includes a first mating member which comprises a body of insulating material of any suitable size and shape. The body carries electrical contact members 26 which extend longitudinally through the body and include a first external portion 30 which is adapted to be permanently secured by welding, riveting, or the like to a portion of the associated electronic circuit 34. The contact members 26 include a second portion 36 which is generally in the form of a rod or pin and is adapted to make electrical contact with a second similar member 42 having corresponding mating parts.

The second member 42 for use with the first member shown also comprises an insulating body 48 having electrical contact members 52 which are embedded in the body and are adapted to receive the contact members 26 of the first member 16. The contact members include external portions 56 similar to the portions of the first mernber to which external electrical connection may be made.

In a typical construction, the contact members 26 might be just a few millimeters in diameter, and the insulating body 20 would be just large enough to receive the contact members. Accordingly, when the first and second mating members 16 and 42 are assembled to provide an electrical connection, it is relatively easy for one part to rotate or move laterally with respect to the other because of the small size and fragility of the contact members. In addition, since the insulating bodies 20 and 48- are only large enough to accommodate the contact members 26 and 52, securing pins or keys, or the like cannot be readily provided. According to the invention, the connection assembly is improved and rendered strong and rugged by means of a sleeve 66 of resilient synthetic resinous material which is fitted over one of the connector members, preferably member 16, the one which is to be permanently secured to a fixed electrical circuit element. The sleeve 66 is of sufiicient length so that it engages and surrounds the insulating body 20 of the connector member and extends longitudinally so that it surrounds portions 36 of the contact members 26 which are to be engaged by the second mating member 42. The sleeve 66 is of a material which can be treated, for example, by the application of heat, to cause it to shrink and harden. One such material is sold by Amp, Inc. under the trademark Ampsulation and comprises polyvinyl chloride.

After the sleeve 66 of resilient material is positioned on the first connector member 16, heat is applied locally to the portion thereof which surrounds the insulating body 20. This portion of the sleeve contracts and hardens to provide a tight, rugged fit with the member 16. The portion 66' of the sleeve which extends longitudinally and surrounds the electrical contact member or pins 36 remains resilient and provides a guide for receiving the second connector member 42 when it is desired to connect the two members together.

The degree of shrinkage of the sleeve 66 depends on several factors including the size relationship between the sleeve and the connector member 16, the thickness of the sleeve, etc. Thus, under some circumstances, the visual shrinkage of the sleeve may be relatively small.

With the resilient portion 66 of guide sleeve 66 surrounding the contact pins 36, the desired connection of the two parts may be made and broken substantially any number of times without danger of the parts rotating or moving laterally with respect to each other and thus becoming broken.

It is clear that various modifications may be made in the specific apparatus shown within the scope of the invention. For example, it is clear that other types of connectors than those specifically shown in the drawing may be provided with resilient guide sleeves in the manner described above.

What is claimed is:

l. Electrical connection means including a first insulating body having first conductive members extending unsupported therefrom,

said conductive members being fragile and movable,

a second insulating body having conductive members embedded therein and adapted to engage the conductive members extending from said first body,

and a sleeve of insulating material surrounding and enclosing said first insulating body and the conductive members extending therefrom,

said sleeve including a first hard, shrunken, rigid portion surrounding said insulating body and a second flexible, larger diameter portion surrounding the conduc- 0 L tive members of said first body and adapted to easily sulating body are hollow tubes adapted to receive said receive said second insulating body whereby the conpins.

ductive members of said second body may engage the conductive members of said second body and said References Cited In the file of thls patent second flexible portion of said sleeve holds said sec- 5 UNITED STATES PATENTS ond insulating body in place. 2,410,321 Watts Oct. 29, 1946 2. The apparatus defined in claim 1 wherein said con- 2,883,520 Sasserson Apr. 21, 1959 ductive members extending from said first insulating body 2,95 8,844 Smith et al. Nov. 1, 1960 are pins and said conductive members in said second in- 3,020,516 Despard Feb. 6, 1962 

1. ELECTRICAL CONNECTION MEANS INCLUDING A FIRST INSULATING BODY HAVING FIRST CONDUCTIVE MEMBERS EXTENDING UNSUPPORTED THEREFROM, SAID CONDUCTIVE MEMBERS BEING FRAGILE AND MOVABLE, A SECOND INSULATING BODY HAVING CONDUCTIVE MEMBERS EMBEDDED THEREIN AND ADAPTED TO ENGAGE THE CONDUCTIVE MEMBERS EXTENDING FROM SAID FIRST BODY, AND A SLEEVE OF INSULATING MATERIAL SURROUNDING AND ENCLOSING SAID FIRST INSULATING BODY AND THE CONDUCTIVE MEMBERS EXTENDING THEREFROM, SAID SLEEVE INCLUDING A FIRST HARD, SHRUNKEN, RIGID PORTION SURROUNDING SAID INSULATING BODY AND A SECOND FLEXIBLE, LARGER DIAMETER PORTION SURROUNDING THE CONDUCTIVE MEMBERS OF SAID FIRST BODY AND ADAPTED TO EASILY RECEIVE SAID SECOND INSULATING BODY WHEREBY THE CONDUCTIVE MEMBERS OF SAID SECOND BODY MAY ENGAGE THE CONDUCTIVE MEMBERS OF SAID SECOND BODY AND SAID SECOND FLEXIBLE PORTION OF SAID SLEEVE HOLDS SAID SECOND INSULATING BODY IN PLACE. 